One Library won't scan

When I try to scan library to update the files, it gives me this pop-up. I’m only having trouble with the one library. I’ve done all the updates as far as I know, and my computer’s obviously connected to the Internet. So I don’t know what the problem is.

Player Version#:

Shut down the server and restart it.
Make sure a usable internet connection is available to the server.

How do I shut down the server? Do I shut down the whole computer?

You use the tray icon
PMS_tray_icon_win10_context_menu

That just made it worse… Now nothing is loading.

Afterwards, you must restart the server from the regular Windows start menu.